describes studies on the catalyticasymmetricintramolecularcyclopropanation (IMCP) of 2-diazo-3-oxo-6-heptenoic acid esters. The enantioselectivity depends on the bulkiness of the ester moiety, and the 2,6-di-tert-butyl-4-methylphenyl ester of 2-diazo-3-oxo-6-heptenoic acid provided the product with 78% ee, suggesting that the catalyticasymmetric IMCP of α-diazo-β-keto esters could be a key reaction
Process for producing 3-cyanomethyl cyclopentanone derivatives
申请人:Sagami Chemical Research Center
公开号:US04100184A1
公开(公告)日:1978-07-11
A process for producing 3-cyanomethyl cyclopentanone derivatives which are useful precursors of fragrant components in jasmine and analogous thereof such as methyl jasmonoate, methyl dihydrojasmonate, etc., is disclosed. In the process, the jasmonoates are produced starting from .beta.-dicarbonyl compounds and azides through several-step reactions.
Process for producing 3-formylcyclopentanone derivatives
申请人:(Zaidanhojin) Sagami Chemical Research Center
公开号:US04073799A1
公开(公告)日:1978-02-14
A novel process for producing 3-formylcyclopentanone derivatives which are useful intermediates for syntheses of five-membered ring compounds such as prostaglandins is disclosed. In the process, 3-formylcyclopentanone derivatives are produced starting from .beta.-dicarbonyl compounds and azides through several-step reactions.
Through a double cyclization triplet carbonylcarbenes add smoothly to double bonds in the δ and ε position, but do not react intramolecularly with C-H bonds (see scheme). The addition reaction fails if the keto group is replaced with an ester group.
Enantioselectively catalyzed intramolecular cyclopropanations of unsaturated diazo carbonyl compounds
作者:William G. Dauben、Robert T. Hendricks、Michael J. Luzzio、Howard P. Ng
DOI:10.1016/s0040-4039(00)97218-6
日期:1990.1
A series of unsaturated α-diazo carbonyl compounds underwent enantioselective intramolecularcyclopropanation (ee = 4–77%) when treated with an enantiomerically pure chiral copper catalyst. The nature of the diazo substrate was critical: α-diazo ketones gave the best enantioselectivities whereas α-diazo β-keto ester systems showed diminished enantioselectivities.